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vincent

1,965 post(s)
#14-Jul-22 19:59

Hi,

Exporting an image from 176.6 and from 172.0 leads to differents outputs. With 172.0, invisibles pixels are loaded as NoData in ArcGIS 10.x. With 176.6, invisibles pixels are loaded as 0 in ArcGIS 10.x

Was this change made on purpose ? Is this a bug ? I think it is not convenient.

Thank you.

Dimitri

7,066 post(s)
#15-Jul-22 06:58

You don't say what format you are using. See release notes for build 9.0.176.4 for TIFF.

adamw


10,126 post(s)
#15-Jul-22 11:16

Could you post example data and say which format you are exporting to so that we could check?

vincent

1,965 post(s)
#15-Jul-22 16:18

Writing a TIFF with floating-point pixels uses NaN for missing pixels.

That should be this. Thank you for pointing the topic. I'll post a file this week.

vincent

1,965 post(s)
#20-Jul-22 19:21

Here is the file : https://drive.google.com/file/d/1KATjO48fZiMqXoe-EwjmW48Cs5e9MWWn/view?usp=sharing

(this is a Manifold 8 file)

In ArcMap 10.8.1, NoData values are NaN. I don't see a way to obtain something else than black pixels, other than exporting the image in .tif from ArcMap.

adamw


10,126 post(s)
#21-Jul-22 07:50

Thanks for the file. Something seems wrong, the image doesn't roundtrip. We'll check what's up.

adamw


10,126 post(s)
#21-Jul-22 08:48

We found the issue. The value written for missing pixels was wrong (a FLOAT32 NaN, not a FLOAT64 NaN). We will fix this.

In the meantime, try converting the image to FLOAT32 and exporting that. (Here's how: open the image, open the Transform pane, select the Tile field, select the Copy template, set the Result combo to New Table, set the tile type to FLOAT32, specify the name of the new image / table components, click Transform.)

vincent

1,965 post(s)
#27-Jul-22 13:27

Same result. ArcGIS list the NoData as NaN, but in the data frame, the value appears as zero. I have pixels with zero as their value, so this is not suitable, because if I set NoData pixels to no color, I'll lost these pixels as well.

I hope this can be fixed.

adamw


10,126 post(s)
#27-Jul-22 14:09

Try using 9.0.177.3 (and exporting the original image, no conversion to FLOAT32 required).

vincent

1,965 post(s)
#27-Jul-22 17:21

Fixed with 177.3. Thank you.

antoniocarlos

609 post(s)
#27-Jul-22 15:41

Hi.

Running this process creates a copy of the original image but the styling is different (a bit darker). One must edit the styling to re-create the same image. Would it make sense to output the copy image with the same styling as the original? This just adds an additional step I know.

Attachments:
image_2022-07-27_114058226.png


How soon?

adamw


10,126 post(s)
#28-Jul-22 09:10

We are considering extending some of the transform templates to copy styles to the new components, yes.

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